Cancer is a global killer of humans with breast cancer and colon cancer among the leaders with many other types killing modest amounts of humans yearly. Breast cancer is the primary killer of women. Colon cancer is the third greatest killer of people in the United States.
Colon cancer although having an excellent cure rate is a very common cancer second only to lung cancer in the United States. 129,400 new cases of colorectal cancer were estimated for 1999 with 56,600 deaths therefrom. The strongest risk factor for colon cancer is age. The incidence rates rise from 10 per 100,000 at age 40-45 to 300 per 100,000 at age 75-80. The cumulative life time risk for the disease is 1 in 20. Men are more likely to develop colon cancer than women. Black Americans are more likely than white Americans to be diagnosed with colorectal cancer. Smokers, drinkers, sedentary, and obese persons are more likely to develop colon cancer.
The U.S. patent literature has many disclosures of oxo-butenoic (crotonic) compounds:    Pamukci (U.S. Pat. No. 6,232,312) describes crotonic acid derivatives (column 22, lines 43-58) for the treatment of colonic polyps;    Jones et al (U.S. Pat. No. 6,121,450) discloses crotonic acid derivatives (column 8, line 34; column 78, line 24 and at example 34 as steroid modifiers in treating breast cancer (column 1, lines 55-58);    Kalden, et al (U.S. Pat. No. 5,334,612) discloses compounds said to be useful for treating AIDS including derivatives of carboxylic acid (column 9, line 31) and pyrrolidine (column 7, line 24);    Brown (U.S. Pat. No. 6,066,670) describes an anti-viral admixture containing crotonic acid for treating tumors (see Abstract);    Horwell, et al (U.S. Pat. No. 5,580,896) discloses many 4-oxo-2-butenoic acid derivatives (column 13, lines 21-59; also in columns 15+, examples 25, 26, 32, 34, 40, 43-46, 77-79, 97, 99, 103, 106,), which are useful for inhibiting colorectal cancer, i.e., colon cancer (Abstract);    Giordani, et al (U.S. Pat. No. 5,580,890) discloses 4-oxo-2-butenoic acid derivatives said to be useful for treatment of AIDS (column 1, line 8 and column 2, line 61; and,    Yonemeto, et al (U.S. Pat. No. 6,083,985) recites a number of anti-tumor or anti-AIDS agents that include butenoic acid derivatives.
The U.S. patent literature has many disclosures of butanoic acid derivatives including:    Nicolai, et al (U.S. Pat. No. 6,180,651) discloses many anti-inflammatory and analgesic compounds, including adenocarcinoma (column 1, line 55), which includes heterocyclic alcohol-esters (column 11, lines 1-16) and butanoic acid derivatives (many Examples including 47 through 162);    Girard, et al (U.S. Pat. No. 5,308,852) discloses many compounds including butanoic acid derivatives (see Methods B and C of schemes II and III) which compounds which are said to inhibit tumor metastasis (column 7, line 56 and column 8, line 4);    Frechette (U.S. Pat. No. 5,696,117), Frechette (U.S. Pat. No. 5,854,242) and Frechette (U.S. Pat. No. 5,707,990) describe 148 benzoxazine and pyrido-oxazine heterocyclic as anti-bacterial compounds;    Omedi-Sale (U.S. Pat. No. 3,862,954) shows tri-azole compounds for CNS use;    Hawkins (U.S. Pat. No. 5,274,002) describes many analogs of phenyl ethers of a substituted phenyl of the formula structure at column 1, lines 49-60 with 37 examples of specific compounds which compounds may be useful for tumor inhibition (column 22, line 64); and,    Boyd, et al (U.S. Pat. No. 6,080,790) also describes many tri-substituted phenyl derivatives according to the formula of the Abstract with 15 examples of specific compounds which may be useful for malignant skin diseases (column 5, line 46).
It appears from a review of the foregoing patents that neither the 2-hydrazino-3-oxo-butenoic acid nor the 2-hydroxy-4-oxobutyric acid derivatives of interest are disclosed and thus there is no report of their activity against human colon cancer.
Consequently, there is a need for an anti-cancer drug for humans that mitigate the above mentioned disadvantages of current drug therapy and effectiveness against the identified human colon cancer.